[GStreamer] Do not use get_mime_codec for <1.20.0

https://bugs.webkit.org/show_bug.cgi?id=294205

Reviewed by Philippe Normand.

gst_codec_utils_caps_get_mime_codec is not available before 1.20.0, so
compile it out conditionally, using tryAutoPlug in that case.

* Source/WebCore/platform/graphics/gstreamer/MediaPlayerPrivateGStreamer.cpp:
(WebCore::MediaPlayerPrivateGStreamer::configureParsebin):

Canonical link: https://commits.webkit.org/296032@main

Author: spenap

Source/WebCore/platform/graphics/gstreamer/MediaPlayerPrivateGStreamer.cpp

@@ -2546,7 +2546,6 @@ void MediaPlayerPrivateGStreamer::configureParsebin(GstElement* parsebin)
         G_CALLBACK(+[](GstElement*, GstPad*, GstCaps* caps, GstElementFactory* factory, MediaPlayerPrivateGStreamer* player) -> unsigned {
             static auto tryAutoPlug = *gstGetAutoplugSelectResult("try"_s);
             static auto skipAutoPlug = *gstGetAutoplugSelectResult("skip"_s);
-            static auto exposeAutoPlug = *gstGetAutoplugSelectResult("expose"_s);
 
             auto name = StringView::fromLatin1(gst_plugin_feature_get_name(GST_PLUGIN_FEATURE_CAST(factory)));
             if (name == "webkitthunderparser"_s && player->m_url.protocolIsBlob())
@@ -2563,6 +2562,8 @@ void MediaPlayerPrivateGStreamer::configureParsebin(GstElement* parsebin)
             if (!isParsed || !*isParsed)
                 return tryAutoPlug;
 
+#if GST_CHECK_VERSION(1, 20, 0)
+            static auto exposeAutoPlug = *gstGetAutoplugSelectResult("expose"_s);
             auto& scanner = GStreamerRegistryScanner::singleton();
             GUniquePtr<char> gstCodecName(gst_codec_utils_caps_get_mime_codec(caps));
             auto codecName = String::fromUTF8(gstCodecName.get());
@@ -2575,6 +2576,7 @@ void MediaPlayerPrivateGStreamer::configureParsebin(GstElement* parsebin)
 
             if (decoderFactoryAcceptsCaps)
                 return exposeAutoPlug;
+#endif
 
             return tryAutoPlug;
         }), this);